Releasing clamp



Jan. 7, 1936. JJM, JESTER 2,026,978

RELEAS ING CLAMP Filed sept. 28, 1952 Patented Jan. 7, 1936 OFFICE RELEASING. QLAMB John Milton Jester, Washington; D:- G. Applica-tion september-2s, 192,2, semi No.; essere 19 Claims.

'I'he invention relates tol clamps for supporting;

high tension transmission lines and has for its general object the provision of a clamp. which( will grip a conductor or cable tightly under normal circumstances but which will, release its grip. upon the occurrence of a strain tendiner toy move the clamp longitudinallyin one direction ort-he other as for example inthe event of breakageo-f the conductor.

It is well known that it is the practice tosupport a high tension conductor, or its equivalent,f

by means of clamps suspended from skeleton towers which are frequently located long distances apart with the result that there is a very: great span between successive clamps used. In monti-- tainous country and inY fact in other places, it`

may occur that an excessive strain comes upon one or more spans for instance as the result. of the accumulation of ice or sleet upon the,con

ductor. In such an event it is obvious that the greatly increased weight of an individual spanor a number of spans will bring a tremendous strain upon the tower beyond the over-weighted; span, there being quite a marked tendency1 to cause the tower to overturn. Under such circumstances. and also in the event of breakage of1 the conduc-v tor it is highly desirable to provide means Vwhere-- by the clamp may release the conductor` and permit it to slip through until the strains are equal ized.

' It is with the above facts in view that I have devised the present invention whichliasv for arr object the provision of a novely and improved.

clamp of this general type and one. whichwillpeitmit a limited displacement of theclamp andr its supporting element from the normal position without releasing the conduotor,it requiring a.

tilting or swinging displacement` beyondY a` certain predetermined limit to eliect theirelease.

A very important object of the invention-is toJ provide a clamp of this character embodyingthe, minimum number of parts, which-willbeentirely free from any springs and, in which, the parts-vare. assembled and held together without any` necessity for the employment of securing elements such as bolts, rivets or anything else of a similar.

nature.

Yet another object is to provide a clamp which has a pivotal connection with a suspension yoke or other support, the axis of the pivot moreover intersecting the conductor so that in the event4 of swaying of the clamp and its support there will be no rocking or tilting tendency.

` Still another object is to provide a clamp off this character in whichthegripping action upon the conductor takes place at the c-ententlie endi portions of the clamp body and also the movable clamping member beingn curved and1flared outwardly away frornthe conductor so as to avoid contact therewith and the bringing of;bending (ClY 248-64) strains; unQn it; the event that the conductor vibrates` ondances` A`v further; object is; to, provide av clampof this character-- which, onaccount of the fewness ofparts will, be extremely simpleand inexpensive 5 tomake, easy tofinstall, positiveain'f` action, emcient and: durables in serviee,v and. a` general improvementin theart.

To the? attainment.. ofv the foregoingi and other objectsy andx advantages, theinvention preferably 10 consists; inthe details'ofL construction and the arrangement andlcombinationofvpartsltobe here--y inafter more fully@ describedfandclaimed, and iilustrated. intthe accompanying drawing; in which:

Figure 1. isla*` viewn partlylfin sideelevationl and.; partly in7 longitudinal section, showingthe clamp, the released position: of they trip member being. Shown by' datand. daslnlinesa and its` operative,v or elective, position? beingV shown by full` linesrl Figure Z isi a centralv verticali cross sectional View with fragmentsein. elevation,v

Eipure; 3` islaI detail, planf View of: the. movable; clamping. member,-

Eigureiissarside elevation thereof-,l

Figurer 5? iS= am elevationT oir that trip, Y and Figure 6 1 isran elevationithereof.- taken at right angles.; to.` Figure: 5.

Referring.L more..A particularly to. the drawing I haveshownthe clampascomprisinga main sup-v porting.; body Ill. preferably longitudinally curved and, reinforced, at.r its;l underside by longitudinalr andtransversewebsl ,l Lands I 2, respectively. This body, is.;` formed, with" a.V transversely curved seatA I3. for.. the.1 receptionof, the. conductor ldand it will, be observedthat.the. endslofr this seat or: groovedportionrareflared outwardly so as'to avoid. contactcwithandtherbringing ofsbending strains upon the conduoton Thesides; |5;of the mainbody of'the clamp are prolonged upwardly anla-p- 40 preciabledistance above. the, conductor. and are formednearoneiendlwith cireulariholes I6 com-- municatingrwthrreducedislots Il openingout at theuppenedges.,'Moreover at .their central por-- tions the y sides;y l 5"arei formed with circular. holes '45 IBL-communicating; withreduced slots. |9- which likewise( openout at the upper., edges.

E01' suspending they device, L have. showni the opposte sides=of-.the;-mainzbedy l fasfformed'with trunnionsyZ 01 w-hiehfa-re rotatably; received withinp50 holesffh in theflowerendsfofisuspension links or the; likeT 2-2s'vvhiolr. aret adapted to 1 be hung from the;lowenend:ofr ai). stringsoffinsulators asv isa customary procedure. The holes 2l are vertically elongatedfso l ast'o :permitl passage; when installationY isbeing#effected;V ofjheads-23fon the ends of the-trunnions; which-heads'overhang downwardly'and'projectlbelow the lower edgesof the openings 2'I so .that'there be no danger of dise 60 connection of the clamp from the suspension means.

The parts thus far described merely support the conductor. To effect clamping thereof I provide an upper clamping member 24 which has its underside somewhat concaved to provide a seat 25 conforming substantially to the conductor. One end of this clamping member is free while the other end is formed at opposite sides with transverse lugs or projections 26 having a thickness corresponding substantially to the width of the slots I1 and having a length corresponding substantially to the diameter of the holes I6, the ends being moreover curved as shown at 21 so as to fit conformingly against the walls of the holes IB.

To mount the movable or upper clamping member 24 or connect it with the main body of the clamp it is necessary to position it in a substantially vertical position and insert the lugs or projections 26 downwardly through the slots I 1 until they enter the holes I6 whereupon this member is swung down into contact with the conductor, the lugs 26 rotating within the holes I6 as this is done. Obviously the clamping member cannot get out of place unless it be swung upwardly into vertical position so that the projections 26 can be withdrawn through the slots I1.

The means cooperating with the clamping member 24 for holding the same in gripping relation to the conductor is represented as comprising a trip cam 2B having its upper portion of V-shape or formed with divergent arms 29 which define the V-shaped opening 39 between them. At opposite sides this trip cam is provided with lugs or projections 3I having their major dimension extending transversely. These projections are of substantially the same width as the slots I9 and have a length of substantially the same diameter as the holes I8, the ends being moreover arcuate as shown at 32 so as to t conformingly against the Walls of the holes I8.

To effect mounting of this trip cam it must be introduced between the sides I5 in a horizontal position as shown by the dot and dash lines in Figure l so that the projections 3| can be passed down through the slots I9 and caused to enter the holes I8, after which the trip cam is swung into the upright position shown by full lines. The lower end of this trip member is of cam shape as shown at 33 in Figure 5 so that when it is turned from the horizontal to the vertical position shown in Figure 1 it will exert a. camming action upon the upper clamping member 24 and Torce the same into gripping engagement with the conductor.

As long as the trip member is in its upright position the clamping. action is maintained, it being clear that to eifect release it is necessary to tilt this member 28 to one side or the other of its normal or vertical position. To effect such release when an excessive strain comes upon the conductor at one side or the other of the clamp I provide the confrontingfaces of the links 22 with lugs 34 which are located within the V-shaped opening 39 of the trip cam normally in spaced relation to the inner faces of the arms 29 thereof so that the clamp and its suspension link may have a limited swinging movement without releasing the conductor. However, it will be seen that in the event of overloading or breakage of the conductor at either side of the clamp the resultant excessive movement of the clamp and its suspension link will cause the lugs 34 to engageY one or the other of the arms 29 and consequently force the trip cam 28 out of its normal or upright position whereupon by virtue of the shape of the cam surface 33 the pressure exerted upon the clamping member 24 will be relieved, thus releasing its clamping engagement upon the conductor so that the conductor may slip through the clamp until 5 the pressure along the conductor is equalized.

From the foregoing description and a study of the drawing it will be apparent that I have thus provided an efcient conductor clamp which is capable of automatically releasing the conductor upon the occurrence of excessive strain. A fea ture of note is that the device embodies but three parts all of which may be constructed as castings and on this account it is manifest thatit may be manufactured at very little cost. It is moreover an important detail that there are no securing members of any sort and that no reliance is placed upon any springs. As normal swinging movement is permissible without release it is evident that there will be no friction between the holding down 2O cam and the upper clamping member and as a result there will be no wear to cause a decrease in the gripping action even after tremendous prolonged use. It is thought from the above that the construction, operation and advantages will be readily apparent to one skilled in the art Without further explanation.

While I have shown and described the preferred embodiment of the invention, it should be understood that the disclosure is merely an exemplication of the principles involved as the right is reserved to make all such changes in the details of construction as will widen the field of utility and increase the adaptability of the device provided such changes constitute no departure from 35 the spirit of the invention or the scope of the claims hereunto appended.

Having thus described the invention, I claim:

l. A conductor supporting clamp comprising a body having a seat for receiving a conductor, an upper clamping member pivoted at one end within the body and engageable upon the top of the conductor, a suspension means connected with the body for supporting the same, a holding down cam pivoted within the body and having a cam surface engaging said upper clamping member, and means on said suspension means cooperating with said holding down cam for moving the same to release its pressure upon the upper clamping member upon swinging movement of the clamp beyond a predetermined limit, the pivots for the upper clamping member and the holding down cam being separate.

2. A conductor supporting clamp comprising a body having a seat for receiving a conductor, an upper clamping member pivoted at one end within the body and engageable upon the top of the conductor, a suspension means connected with the body for supporting the same, a holding down cam pivoted within the body and having a cam surface engaging said upper clamping member, means on said suspension means cooperating with said holding down cam for moving the same to release its pressure upon the upper clamping member upon swinging movement of the clamp beyond a predetermined limit, said last named means providing projections on the confronting sides of the suspension means, and divergent arms on said holding down cam located at opposite sides of said projections in spaced relation thereto, the pivots for the upper clamping member and the holding down cam being spaced apart longitudinally of the clamp.

3. A conductor supporting clamp comprising a body having a seat for receiving a conductor, an

iol

upper Clemens memberlpivvted at @resend Within the. b o'r @d ageablsupoil f1.1? 120D 0f the conductor, a suspens onL means connected with the body for 'supporting the same, a holding down cam pivoted within the body', and having a cam surface engagingl said upper clamping member, and meansV on said suspensionv means cooperating wiith said holding down camV for moving the same tov releas'efits 'pressuren upon the upper clamping member'up'on, swinging movement of the clamp beyondI a predetermined limit, 'said upper clamping member and said. holding down cam having integral means thereon pivotally received within th'e'sides of the body.

4L Aconductor clamp comprising a main body having a seat adapted to receive a conducto-r, an upper'clamping member located between the sides of said body and 'engageable with the conductor, suspension means connected withv the body for supporting the same, a cam located between the sides oi the body and having a cam surface engaging said clamping member, and means on the suspension means engageable with said cam for moving ythe same out of clamping relation t0 the f-lmlng member upon swinging movement of the clamp beyond a predetermined extent, said clamping member and said cam having integral trunnions thereon pivotally engaged within the sides of the body, and means on the sides of y the body preventing disconnection of the clampan elongated body having a seat between its sides for engagement beneath a conductor, the sides having circular openings communicating with slots opening out to the top, a clamping member engageable upon the conductor and` provided at one end with trunnion lugs insertable through said slots and rotatably engageable within the openings, a cam pivoted between said sides and having its lower portion formed with a cam surface engaging said clamping member and having its upper portion provided with upstanding arms, suspension means for said body, and means on said suspension means located between said arms and engageable therewith for tripping said cam upon swinging movement of the device beyond` a predetermined extent.

6. A conductor supporting clamp comprising an elongated body provided between its sides with h the conductor and having its upper portion formed with spaced arms, suspension means for the body, and means onsaid suspension means located between said arms and engageable therewith for tripping said cam upon swinging movement of the clamp beyond a predetermined extent.

7.. A conductor supporting clamp comprising an elongated body having a seat between its sides for engagement beneath a conductor, the sides having circular openings communicating with slots openingout togtheltop, a clamping member extension on the trip camior releasing the saine" upon swingingfmoyeinentfc'fthe clamp beyond a predetermined' eiit'erlt. t

8, A co''nductorsupportingk clamp comprising a lower clamping. engageable beneath a conductor and having spacedupstanding sides, an upper rclamping member disposed between said sides and bearing upon thetop of the conductor, trunnion`meansfomed integrally upon one end of the` upperdclamping member and removably and'pivotally. engagedwithin openings inthe sides of the lowerrclamping membenvandmeans mounted between the sides ofthe lower clamping men ber above thefupperclampin'g member for maintaining thev same nornlially in engagementr with the conductor. l

9'. A conductor clamp comprising a lower clamping member adapted tc receive a conductor and having spaced upstanding sides each formed near one end Withfa 'circular opening anda constricted slot leading therefrom to the upper edge of the side, an upper clamping member-disposable against the top ofthe conductor and lying between said sides, said upper clamping member being provided at one end with trunnions movable alongr said slotsY when the upper clamping memberis in disengaged. relation to the conductor and rotatably'engaged within said circular and having spaced upstandingsides each formed f near one end with` acircular opening and a constricted slot leading. therefrom to the upper edge of the side, an. upper clamping member disposable againstthe topor the conductor and lying between said sides ,lsaid upper'clamping member being provided at oneend with trunnions movable along said slots`-when the upper clamping member is in disengagedrelaticn to the conductor and rotatably engaged within said circular openings when the upper clamping member f is in clamping relation to the conductor, and means reacting against the intermediate portion of the upper clamping member for normally main'- taining its clamping relation,r said means being detachable when in ineffective position.

11. A conductor clamp comprising a lower clamping member adapted to receive a conductor and having spaced upstanding sides each formed near one end with a circular opening and a constricted slot leading therefrom to the upper edge of the side, an upper clamping member disposable against the top of the conductor and lying between said sides, said upper clamping memberv beingv provided at one end with trunnonsmovable. along said@ slots.,v when thev upper clamping member is in disengaged relation to the conductor and rotatably engaged within said circular openings when the upper clamping member is in clamping relation to the conductor, and means reacting against the intermediate portion of the upper clamping member for normally maintaining its clamping relation, said means comprising a holding down cam pivoted between said sides and disengageable therefrom when in ineffective position.

12. A conductor clamp comprising a lower clamping member adapted to receive a conductor and having spaced upstanding sides each formed near one end with a circular opening and a constricted slot leading therefrom to the upper edge of the side, an upper clamping member disposable against the top of the conductor and lying between said sides, said upper clamping member being provided at one end with trunnions movable along said slots when the upper clamping member is in disengaged relation to the conductor and rotatably engaged within said circular openings when the upper clamping member is in clamping relation to the conductor, and means reacting against the intermediate portion of the upper clamping member for normally maintaining its clamping relation, said means comprising a holding down cam having oppositely extending trunnions with attened sides normally rotatably engaged within circular openings in said sides, said sides having slots leading from said last named circular openings to the upper edges to permit passage of said second named trunnions when said holding down cam is in ineffective position.

13. A conductor clamp comprising a lower clamping member adapted to receive a conductor and having spaced upstanding sides, an upper clamping member located between said sides for engagement with the top of said conductor, and a holding down cam mounted between said sides and reacting against said upper clamping member for maintaining it normally in clamping relation to the conductor, said holding down cam being formed with oppositely extending trunnions having attened sides, and the sides of the lower clamping member being formed with circular openings and reduced slots leading therefrom to the upper edges, said circular openings receiving said trunnions when the said holding down cam is in normal or eiective position reacting against the upper clamping member and being withdrawable through said slots when the holding down cam is partially rotated into ineffective position with respect to the upper clamping member.

14. In a conductor supporting clamp, a lower clamping member for receiving a conductor and having upstanding sides, suspension means connected with said lower clamping member, a holddown cam mounted between said sides and reacting toward the conductor, and an upper clamping member located between the sides and beneath said cam for engagement with the conductor, and means pivotally connecting one end of said upper clamping member to the sides of the lower clamping member, said means being formed as integral lateral projections on the upper clamping member received within openings in said sides.

15. In a conductor supporting clamp, a lower clamping member for receiving a conductor and having upstanding sides, suspension means connected with said lower clamping member, a holdV down cam mounted between said sides and reacting toward the conductor, and an upper clamping member located between the sides and beneath said cam for engagement with the conductor, and means pivotally connecting one end of said 5 upper clamping member to the sides of the lower clamping member, said means being formed as lateral projections on one end of the upper clamping member, said sides having keyhole slots receiving said projections and permitting with- 10 drawal thereof when the upper clamping member is swung away from the conductor.

16. In a conductor supporting clamp, a lower clamping member for receiving a conductor and having upstanding sides, suspension means con- 15 nected with said lower clamping member, a holddown cam mounted between said sides and reacting toward the conductor, and an upper clamping member located between the side-s and beneath said cam for engagement with the con- 20 ductor, and means pivotally connecting one end of said upper clamping member to the sides of the lower clamping member, said means being formed as lateral projections at one end of the upper clamping member, said projections having 25 two opposite sides flat and their opposite edge portions curved, said sides having curved openings rotatably receiving and retaining said projections and further having reduced slots extending from said openings to the upper edges of the sides 30 of the lower clamping member for permitting passage and withdrawal of said projections from engagement with the lower clamping member when the upper clamping member is swung on its pivot away from the conductor. 35

17. In a conductor clamp, a lower clamping member for receiving a conductor and having spaced upstanding sides, an upper clamping niember located between said sides for clamping engagement with the conductor, a. hold-down cam 4,0 located between said sides for cooperation with the upper clamping member to hold the same in engagement with the conductor, and means integral with said cam and rotatably and detachably engaged within openings in said sides. 4,5

18. In a conductor clamp, a lower clamping member for receiving a conductor and having spaced upstanding sides, an upper clamping member located between said sides for clamping engagement with the conductor, a hold-down cam 50 located between said sides for cooperation with the upper clamping member to hold the same in engagement with the conductor, and lateral projections carried by said cam and rotatably and detachably received within keyhole slots in 55 the sides of the lower clamping member.

` 19. In a conductor clamp, a lower clamping member for receiving a conductor and having spaced upstanding sides, an upper clamping member located between said sides for clamping en- 50 gagement with the conductor, a hold-down cam located between said sides for cooperation with the upper clamping member to hold the same in engagement with the conductor, projections extending laterally from both sides of said cam, said projections having diametrically opposite sides flat and their opposite edges curved, and said sides having circular openings receiving and normally containing said projections and further having reduced slots leading from the openings to the upper edges for permitting passage and withdrawal of the projections when the cam is rotated out of its normal position.

JOHN MILTON JESTER. n 

